As the Nokia vs Qualcomm shoot-out opens later today in a Delaware courtroom, a German court has ruled that a Qualcomm’s GSM patent is invalid.

Qualcomm has pursued 11 law actions against Nokia for infringement of GSM patents and the German court is the third court, after the US International Trade Commission and the UK High Court, to rule that the patents asserted to have been infringed are either invalid or have not been infringed.

Nokia pointed out that the decision was further evidence that Qualcomm ‘overstates its role as a wireless innovator’ and does not have enforceable or relevant GSM patents.

The Delaware case relates to CDMA patents. Nokia says it paid $1bn in royalties to Qualcomm for CDMA patents but ceased to do so when these expired.

Qualcomm acknowledges that the original patents expired, but says it has new patents on CDMA on which Nokia should pay royalties. Nokia says the new patents do not justify royalty payments at the old rate and has been putting aside $20m a quarter to pay for royalties on the new patents.

Qualcomm alleges that, by using technology associated with the new patents, Nokia has, by implication, extended the licence agreement on the old patents and should pay royalties at the old rate.

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